1. Field of the Invention
The present invention relates to a determination apparatus and a determination method for determining whether the quality of an image signal outputted is good or not.
2. Description of Related Art
Shortening of a manufacturing cycle and a reduction of the manufacturing cost are required for a process for manufacturing an electronic device or the like. Therefore, the cost reduction, quality improvement, and speed-up are also required even for the manufacturing tests of the electronic devices etc.
Up to now, in a manufacturing test process for an electronic device or the like, a display check test for an LCD or the like is performed by visual check by a person. However, the display check performed by the person depends on his/her skills and experiences. Therefore, a check failure or a judgment error may occur in the display check performed by the person. In addition, the display check performed by the person takes a time. Further, the display check performed by the person may cause additional steps.
Therefore, methods eliminating the display check performed by the person have been devised. For example, an apparatus capable of automatically checking an electronic device without a visual check performed by a person in steps of manufacturing and checking the electronic device has been devised (see Patent document 1).
[Patent document 1] JP 2001-184018 A
[Patent document 2] JP 2004-199536 A
In the conventional apparatus eliminating the visual check performed by the person, for example, an LCD display signal is temporarily captured in a high-speed RAM. Then, the conventional apparatus compares a value captured in the high-speed RAM with an expected value stored in advance in a medium-speed RAM. Therefore, the conventional apparatus requires two kinds of RAMs such as one for signal capture and one for expected value storage. Thus, there is a problem in that a cost of the conventional apparatus becomes higher.
Besides, recently, high-resolution LCDs having higher resolutions than XGA have been popularized. Therefore, the conventional apparatus requires a higher-speed and larger-capacity memory. As a result, there is a problem in that the conventional apparatus becomes further costly. In addition, the conventional apparatus has such a structure that the LCD display signal is captured in the memory and then the value of the captured signal is compared with the expected value. Therefore, there is a problem in that the period of time for testing the conventional apparatus becomes long.
Furthermore, the conventional apparatuses use one pixel data of image data as data indicating a display pattern. Therefore, in the conventional apparatus, the pixel used for the display pattern cannot be subjected to the display check test. With respect to this point, according to the description of the conventional apparatus, there is no practical trouble. However, when abnormality occurs in the pixel used for the display pattern, the data of the display pattern does not become the one to be intended. Therefore, there is a fear in that the conventional apparatus erroneously determines a non-defective product to be a defective product.
The present invention has been made in view of the circumstances and an object of the present invention is to provide a determination apparatus and a determination method which are capable of determining whether the quality of a signal outputted from a testing object is good or not.